Justin Bieber I WON'T Turn My Back On Lil Twist and Lil Za

7/12/2013 1:00 AM PDT

Justin Bieber -- I WON'T Turn My Back on Lil Twist, Lil Za

EXCLUSIVE

Justin Bieber refuses to throw Lil Za and Lil Twist out on the street ... even after all of the trouble they've caused ... because he considers them "true friends" ... TMZ has learned.

Sources close to Bieber tell TMZ ... members of Justin's camp have been pleading with him to boot the Lils out of his Calabasas home and forbid them from driving his fleet of fancy cars after a string of embarrassing incidents including Twist's DUI arrest in JB's car.

We're told Bieber's camp has been very concerned about the way he acts when he's with the Lil crew -- and have been vocal that the guys are a bad influence.